Search for the X (5568) State Decaying into B[superscript 0][subscript s] π[superscript ±] in Proton-Proton Collisions at √ s = 8 TeV

Abstract

A search for resonancelike structures in the B[subscript s][superscript 0] π[superscript ±] invariant mass spectrum is performed using proton-proton collision data collected by the CMS experiment at the LHC at √s =8 TeV, corresponding to an integrated luminosity of 19.7 fb[superscript -1]. The B[subscript s][superscript 0] mesons are reconstructed in the decay chain B[subscript s][superscript 0]→J/ψϕ, with J/ψ→μ[superscript +]μ[superscript -] and ϕ→K[superscript +]K[superscript -]. The B[subscript s][superscript 0]π[superscript ±] invariant mass distribution shows no statistically significant peaks for different selection requirements on the reconstructed B_{s}^{0} and π[superscript ±] candidates. Upper limits are set on the relative production rates of the X(5568) and B[subscript s][superscript 0] states times the branching fraction of the decay X(5568)[superscript ±]→B[subscript s][superscript 0]π[superscript ±]. In addition, upper limits are obtained as a function of the mass and the natural width of possible exotic states decaying into B[subscript s][superscript 0]π[superscript ±].